ROS:Constitutional: no f/c, no wt lossEyes: No visual changes, eye pain or discharge.ENMT: No hearing changes, pain, discharge or infections. No neck pain or stiffness.Cardiac: No chest pain, SOB or edema. No chest pain with exertion.Respiratory: No cough or respiratory distress. No hemoptysis.GI: see HPIGU: No dysuria, frequency or burning.MS: No myalgia, muscle weakness, joint pain or back pain.Neuro: No headache or weakness. No LOC.Skin: No skin rash.

A FAST was performed upon patient’s arrival. The following images below (Images A and B) were obtained. What do you notice? (RUQ, LUQ)

Patient’s b-hCG was 31.31. At what b-hCG level is an IUP detectable on transvaginal US (discriminatory zone)?

What is the first definitive sign of pregnancy on bedside US?

What is the differential in a case of failure to identify a yolk sac/fetal pole in the uterus of a pregnant patient?

Further US of the pelvis showed the following image below (Image C). What is your main concern? What is your next course of action?

ANSWERS:

Images A and B demonstrate free fluid in the RUQ and LUQ.

b-HCG of 1,500 is considered the discriminatory zone, i.e. minimum quantitative level of HCG at which an intrauterine pregnancy should be seen by ultrasound. ***However, ectopic pregnancy DOES NOT follow the rules. If the b-HCG is not 1500, there is still a possibility of an ectopic pregnancy. The adnexa should always be visualized to assess for a possible ectopic regardless of the b-HCG.

A gestational sac appearing as a thin walled sac within the uterus is NOT definitive evidence of an intrauterine pregnancy, as it could also represent a pseudogestational sac, which could be a decidual cyst or endometrial breakdown during an ectopic pregnancy. Definitive sonographic evidence of an intrauterine pregnancy is established when a yolk sac is identified in two planes within a gestational sac in the uterus.

The circular ring noted in the pelvis in the setting of a positive FAST exam and a positive b-HCG is concerning for an ectopic pregnancy until proven otherwise. Your next course of action should be to stabilize patient, fluids, labs (Including T&S) and immediately involve OB/Gyn service.